Thermoelectric dehumidifier and reheater



March 31, 1964 A. P BOEHMER ET AL THERMOELECTRIC DEHUMIDIFIER AND REHEATER 2 Sheets-Sheet 1 Filed June 19, 1962 fnvenZ or-v'" Q'rzdfezu f? fioekmer 0 502456226 M Jar-smug -xf% United States Patent 3,126,710 THERMOELECTRHC DEHUMlDliFllER AND REHEATER Andrew P. Boehmer, Des ilaines, and Boubene M.

Jaremus, Barrington, Ill., assignors to Borg-Warner Corporation, Chicago, 1111., a corporation of Illinois Filed June 19, 1962, Ser. No. 203,644 2 Claims. (Cl. 62-3) The present invention relates to an apparatus for removing water vapor from air and more particularly to dehumidifiers that provide for the use of thermoelectric couples to accomplish this purpose.

In order to extract moisture from the surrounding atmosphere, a column of ambient air is caused to fiow through the cold fins of the thermoelectric couples to thereby condense the vapor from the air. No moving parts are required thus insuring quiet operation. Furthermore, it lends itself to compactness and small size and capacity as compared to the vapor compression type dehumidifiers.

It is therefore an object of the present invention to provide a dehumidifier that operates silently.

It is a further object of the present invention to provide a silent dehumidifier that is compact, lends itself to small capacity, and operates at a high efficiency.

In accordance with the present invention a source of DC. power is connected to thermoelectric couples within a casing through which vertical columns of air flow. An air inlet is provided in its upper portion with air outlets on either side thereof also in its upper portion. A column of air entering the casing passes between the cooling tins of the thermoelectric couples which condenses the water vapor in the air column thus extracting portions of it whereby the air becomes cooler and more dense. The air then reverses its flow at the bottom of the container and travels upwards through channels which have the hot fins of the thermoelectric couples extending therein. The air thus flows between these hot fins, becomes heated and passes to the atmosphere. Heating these air columns also provides more buoyancy to the air because of lessened density which enhances its upward flow through the top of the container, thus producing a steady chimney effect. By maintaining the same direction of flow of the air column entering the unit, and likewise of the air columns discharged from the unit, the maximum fin area is contacted by the moving air, and operation at maximum efiiciency is thus attained.

The invention consists of the novel constructions, arrangements and devices to be hereinafter described and claimed for carrying out the above stated objects and such other objects as will be apparent from the following description of preferred forms of the invention, illustrated with reference to the accompanying drawings, wherein:

FIGURE 1 is an elevational view of a dehumidifier embodying the present invention;

FIGURE 2 is an enlarged cross section view taken on line 22, of FIGURE 1;

FIGURE 3 is an enlarged elevational cross section taken on line 3-3, of FIGURE 2;

FIGURE 4 is a fragmentary sectional view taken on line 4-4, of FIGURE 3 and FIGURE 5 is a schematic diagram of a dehumidifier with its power supply embodying the present invention.

Like characters of reference indicate like parts in the several views.

A dehumidifier comprising a casing 11 open at the top, which may be formed, for example, from a sheet of metal, is provided with a pair of fin base plates 12 and 13 each having a pair of lugs 14 and 15, and 16 and 17, respectively, by which they are attached to a base 18 of 3,126,710 PatentedMar. 31, 1964:

2 the casing 11 by bolts 19 and 20, and 21 and 22, respectively.

These fin base plates 12 and 13 thus provide a partition between side walls 23 and 24 of the casing 11 which in turn provide an intake channel, or compartment, 25 therebetween and a pair of exhaust channels, or compartments, 26 and 27 on the opposite sides thereof. Each of the fin base plates 12 and 13 is provided with openings 23 and 29, respectively, at their lower ends as illustrated by opening 28 in FIGURE 4 thereby aifording communication between the channels. Heat dissipator fins 30 and 31 extending into the exhaust channels 26 and 27, respectively, are connected to the fin base plates 12 and 13, respectively, which extend upwardly through the opening in the casing 11 and have attached thereto a handle 32 at their upper medial portions.

A first set of thermoelectric modules 33 is clamped between the fin base plate 12 serving as a supporting structure and a fin base plate 34 which is provided with heat absorber fins 35 extending into the intake channel 25. A second set of thermoelectric modules 36 is clamped between the fin base plate 13 serving as a supporting structure and a fin base plate 37 which is provided with heat absorber fins 38 extending into the intake channel 25. Any suitable means for clamping the thermoelectric modules between the fin base plates may be used, as for example, bolts 39. Electrical insulation between the modules and the base plates, not shown, is provided, which is in accordance with common practice.

The upper limits of the fin base plates 34 and 37 are on a plane, substantially that of the top of the casing 11, and extend downwardly to a point substantially that of the top of the openings 28 and 2%, respectively.

Insulation 40 is provided between the fin base plates in the areas between the thermoelectric modules and in the areas of the side walls 23 and 24 adjacent to the intake channel 25.

The power supply comprises a filter choke 41 located in an enlarged portion 42 of the exhaust channel 26, a transformer 43 located in an enlarged portion 44 of the exhaust channel 26 and a pair of rectifiers 45 and 46, one each connected in an electrically isolated manner to the upper end of a medial fin of the set of heat dissipator fins 3d and 31, respectively.

The base 18 of the casing 11 is provided with a dropped center providing a basin 47 for the accumulation of condensed moisture which is drained therefrom by a drain pipe 48. Legs 49, only two of which are shown, are attached to the base 18 of the casing 11.

A pilot 5b and an off-on switch 51 are connected with respect to the enlarged portion 44 of the exhaust channel 27. The connections of these two units and the power supply units in the electric circuit are shown schematically in FIGURE 5.

The thermoelectric modules 33 and 36 comprise heat pumps. When an electric current is passed through the electrical circuit cold and hot junctions are formed in accordance with the well-known Peltier effect. The hot junctions are connected to the fin base plates 12 and 13 to which the heat dissipator fins 30 and 31, respectively, are connected and the cold junctions are connected to the fin base plates 34 and 37 to which the heat absorber fins 35 and 38, respectively, are connected.

The top of the casing 11 being open, columns of air flow down the intake channel 25 and the exhaust channels 26 and 27. Since the column of air in the intake channel 25 is exposed to the heat absorber fins 35 and 38 which are connected with respect to the cold junctions of the thermoelectric modules 33 and 36, respectively, condensation of the moisture in the column of air occurs. Moisture thus extracted from the air is deposited in the J basin 47 from which it is drained by drain pipe 48. The air thus becomes cooled and has greater density which enhances its downward movement.

Since the columns of air in the exhaust channels 26 and 27 are exposed to the heat dissipator fins 30 and 31, respectively, which are connected with respect to the hot junctions on the thermoelectric modules 33 and 36, respectively, the columns of air in the exhaust channels 26 and 27 are heated causing these columns of air to rise. A chimney effect is thus produced which causes a column of air to move through the top of the intake channel 25 downwardly between the heat absorber fins 35 and 38 where moisture is extracted and deposited in the basin 47. The column of air partially dehydrated then moves through the openings 28 and 29 and is heated as it moves upwardly in the exhaust channels 26 and 27 which provide a chimney effect.

While this invention has been described in connection with a specific embodiment thereof, it is to be understood that is by way of illustration and not by way of limitation and the scope of this invention is defined solely by the appended claims which should be construed as broadly as the prior art will permit.

We claim:

1. A dehumidifier comprising:

a casing;

a first thermoelectric panel, having a first surface which is heated and a second surface which is cooled as electrical energy is supplied to the panel, a plurality of heat-dissipating fins affixed to the heated surface and a plurality of heat-absorbing fin segments afiixed to the cooled surface;

a second thermoelectric panel, having a first surface which is heated and a second surface which is cooled as electrical energy is supplied to the panel, a plurality of heat-absorbing fin segments affixed to the cooled surface of said second panel and extending toward the heat-absorbing fin segments of the first panel, and a plurality of heat-dissipating fins affixed to the heated surface of the second panel,

said casing and panels defining a vertically extending cooling channel around the heat-absorbing fin segments, including an upper inlet where the direction of the incoming air is the same on each side of the inlet to provide maximum cooling, and a pair of connecting apertures at the lower portion of the cooling channel,

said casing and panels further defining a pair of vertically extending air heating channels around the heatdissipating fins, each heating channel receiving cooled air from one of said connecting apertures and having an upper outlet where the direction of the outgoing air is the same on each side of the outlet;

and means for supplying electrical energy to said panels to operate the dehumidifier.

2. A dehumidifier comprising:

a casing;

a first set of thermoelectric modules, secured between a pair of fin base plates, and oriented to heat the first of said base plates and cool the second of said base plates responsive to passage of unidirectional electrical energy through said modules;

a second set of thermoelectric modules, secured between third and fourth fin base plates, arranged substantially parallel to said first set of modules with said third base plate facing said second base plate, and oriented to cool said third base plate and heat said fourth base plate responsive to passage of unidirectional electrical energy through said second set of modules;

a plurality of heat-absorbing fins affixed to said second and third base plates;

a plurality of heat-dissipating fins affixed to said first and fourth base plates;

means, including said casing and said second and third fin base plates, for defining an air cooling channel in which all of the second and third base plates, including the end portions at the entrance to said channel, are exposed to maximum air flow;

means, including said casing and said first and fourth fin base plates, for defining a pair of spaced-apart air heating channels in which all of the first and fourth fin base plates, including the end portions at the outlets of said heating channels, are exposed to maximum air fiow;

means, including one of said first and second base plates and one of said third and fourth base plates, defining openings between the air cooling channel and each of said air heating channels;

and means for passing unidirectional electrical energy through said first and second sets of thermoelectric modules, whereby air passing through said cooling channel is cooled and becomes more dense, the dense air passing through said openings for heating in the pair of heating channels and subsequent discharge from the dehumidifier.

References Cited in the file of this patent UNITED STATES PATENTS 

1. A DEHUMIDIFIER COMPRISING: A CASING; A FIRST THERMOELECTRIC PANEL, HAVING A FIRST SURFACE WHICH IS HEATED AND A SECOND SURFACE WHICH IS COOLED AS ELECTRICAL ENERGY IS SUPPLIED TO THE PANEL, A PLURALITY OF HEAT-DISSIPATING FINS AFFIXED TO THE HEATED SURFACE AND A PLURALITY OF HEAT-ABSORBING FIN SEGMENTS AFFIXED TO THE COOLED SURFACE; A SECOND THERMOELECTRIC PANEL, HAVING A FIRST SURFACE WHICH IS HEATED AND A SECOND SURFACE WHICH IS COOLED AS ELECTRICAL ENERGY IS SUPPLIED TO THE PANEL, A PLURALITY OF HEAT-ABSORBING FIN SEGMENTS AFFIXED TO THE COOLED SURFACE OF SAID SECOND PANEL AND EXTENDING TOWARD THE HEAT-ABSORBING FIN SEGMENTS OF THE FIRST PANEL, AND A PLURALITY OF HEAT-DISSIPATING FINS AFFIXED TO THE HEATED SURFACE OF THE SECOND PANEL, SAID CASING AND PANELS DEFINING A VERTICALLY EXTENDING COOLING CHANNEL AROUND THE HEAT-ABSORBING FIN SEGMENTS, INCLUDING AN UPPER INLET WHERE THE DIRECTION OF THE INCOMING AIR IS THE SAME ON EACH SIDE OF THE INLET TO PROVIDE MAXIMUM COOLING, AND A PAIR OF CONNECTING APERTURES AT THE LOWER PORTION OF THE COOLING CHANNEL, SAID CASING AND PANELS FURTHER DEFINING A PAIR OF VERTICALLY EXTENDING AIR HEATING CHANNELS AROUND THE HEATDISSIPATING FINS, EACH HEATING CHANNEL RECEIVING COOLED AIR FROM ONE OF SAID CONNECTING APERTURES AND HAVING AN UPPER OUTLET WHERE THE DIRECTION OF THE OUTGOING AIR IS THE SAME ON EACH SIDE OF THE OUTLET; AND MEANS FOR SUPPLYING ELECTRICAL ENERGY TO SAID PANELS TO OPERATE THE DEHUMIDIFIER. 